


Squared

by jessalae



Series: Advanced Mathematics for the Casual Time Traveler [3]
Category: Doctor Who (2005)
Genre: Other
Language: English
Status: Completed
Published: 2012-06-06
Updated: 2012-06-06
Packaged: 2017-11-07 02:00:45
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,952
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/425673
Author URL: https://archiveofourown.org/users/jessalae/pseuds/jessalae
Summary: <blockquote class="userstuff">
              <p>After a while, though, one of the ideas that he had tried to stow away kept wriggling its way to the front of his mind: himself and the Doctor with Amy in the middle, both of them buried inside her, three parts of one whole.</p>
            </blockquote>





	Squared

**Author's Note:**

> Originally posted on my Dreamwidth December 25, 2010.

Logistics had never really been Rory’s strong suit. Wedding planning had been a nightmare: Amy hadn’t been very interested in figuring out anything but her dress and the music, and once she had stepped out of the picture there had been her mother and aunt and Rory’s mother all hounding him at once for his opinions on the guest list and the reception hall and the best man's cufflinks and who knows what else. He'd given his input until he had nothing left to put in, and wondered why there had a be such a big fuss when all he wanted to do was marry the woman of his dreams.

All those decisions, though, had been so much icing on the cake of spending the rest of his life with Amy. He’d been bad at them because they really weren’t the point. In the weeks since he and Amy had brought the Doctor into their bed, Rory had found he could be quite good at logistics when they were the central issue — say, whose limbs went where and when.

He found himself dreaming about positions that he’d dismissed as contrived when he saw them in pornos and looking appraisingly at any vaguely flat surface. The addition of one more person to their sex life exponentially increased the possibilities. Some ideas he suggested as soon as he thought of them, like the time the gravity circuit in the console room malfunctioned and they had sex suspended in midair, their clothes floating quietly around them. Others, like his newly acquired fascination with tentacles, he stored neatly in the back of his head, hoping he’d have an opportunity to bring them one up one day. After a while, though, one of the ideas that he had tried to stow away kept wriggling its way to the front of his mind: himself and the Doctor with Amy in the middle, both of them buried inside her, three parts of one whole. He imagined the press of their bodies, double rhythm of their thrusts, the heat of Amy’s body and the Doctor’s mouth. It was more than intriguing, it was fascinating, and every time he thought about it, it seemed more and more like the perfect thing for them to do. When he woke up for the third night in a row soaked in sweat and hard as a rock, images of the three of them completely entwined fading slowly from his mind’s eye, he knew he had to do something about it.

He was cautious about broaching the subject with Amy; the first time he’d brought up anal sex, possibly too early in their relationship, she’d said, "Fine, as long as I can return the favor," and started looking at strap-ons online in a cheerful but menacing sort of way. A few years down the line, Rory wasn’t too concerned about that anymore, but he still thought it best to tread carefully.

For whatever reason, the opportune moment arose when they were in the swimming pool again, after a trip to the purple desert planet of Talitha Borealis had made them all feel like they needed to wash a layer of grit off their skin. Amy was under the waterfall, the sheets of water fracturing around her shoulders and the top of her head and spraying out in a fine mist. Rory left the Doctor doing laps around a large piece of brain coral and swam over to her, the roar of the waterfall making it pointless to call her name.

Rory grabbed her by the wrist and pulled her into the little cave behind the falls, where it was actually much quieter, the water cutting off their view of the rest of the pool and making a private little corner.

"Hello, you," Amy said, grinning. "You've still got purple behind your ears." She splashed water at his head, not aiming very precisely.

"I have a question," Rory spluttered, shaking his head to fling the droplets out of his eyes.

"And I may have an answer," Amy said, hoisting herself up on a little granite outcropping.

Rory pushed himself up beside her and took a deep breath. "So I’ve been thinking about our sex life," he began.

“Now that’s a terrifying phrase,” Amy said, smirking.

“Yes, I know, but seriously,” Rory said. “I’ve been thinking. Well, more like fantasizing.”

“Oh? Do tell.” Amy crossed her legs and leaned forward coyly.

"And I don’t know if you’re going to go for this,” Rory said, forging on ahead as if she hadn’t spoken, “So I thought I’d bring it up with you before I even mentioned it to the Doctor, because it would just be awkward if I told him before you and then you weren’t interested. And it’s perfectly all right if you aren’t interested, I love what we’re doing anyway and I’d love you even if we weren’t doing anything, so—”

“Rory. What is it?” Amy asked flatly.

“Double penetration,” Rory said in a rush. “I’d like — I’d like to try it with me and the Doctor both inside you. At once. I think—” he swallowed hard. “I can’t stop thinking about it, I think it’d be brilliant. And I was hoping you’d think so too?”

Amy cocked her head to the side and looked at him. “You’re so cute when you babble,” she said, slinging her arms around his neck. “And you have _excellent_ ideas.”

“Oh,” Rory said. “Is that a yes, then?”

“Yes it’s a yes,” she said. “Now let’s go tell the Doctor.” She slid off the rock and ducked through the waterfall. Rory followed her, surfacing just far enough away from the pounding water to hear her yell, “Oi, Doctor! Rory’s got a proposition for you!”

They met up at the side of the pool, and the Doctor looked expectantly at Rory, who suddenly found himself at a loss for words.

“You said to tell you when we wanted something,” he said, since that seemed as good a starting place as any. “So this is me. Telling you. That. Um.”

Amy elbowed him none too gently, but he’d never been good at talking sex, and especially not with the Doctor, who for all his enthusiasm in the bedroom still looked like a mad professor and acted like a five-year-old most of the time. A few more stammered syllables and he gave up entirely.

“Maybe it’s better if we show you, hm?” he said, pulling Amy between them and kissing her.

The Doctor floated on the other side of them, looking bemused, until Rory broke the kiss and pulled him against them, kissing him over Amy’s shoulder. Amy pivoted, mouthing hotly against the Doctor’s chest and wrapping her legs around his waist. Rory caressed down the length her body and over her bum, his fingers tangling with the Doctor’s when he reached her thighs.

The Doctor looked at him with wide, understanding eyes. “Ah,” he said, and kissed Rory again.

At some point Amy let go of the side of the pool to run her hands over Rory’s sides and all three of them sunk under the water. They came up spluttering, but reached for each other again, until the Doctor held up a finger to block Amy’s kisses and said, “I think we’d better take this to the bedroom,” low and hoarse and unbelievably sexy.

Some days Rory couldn’t quite believe how lucky he was.

They left their wet bathing suits on the bedroom floor and leapt into bed. Amy had started arching into Rory’s hands on her bum, so Rory grabbed the lubricant from the bedside table, spreading the cheeks of Amy’s arse with his other hand.

“Is this okay?” he breathed hotly in her ear, pressing against her arsehole with one slick finger.

“Oh, yes,” she murmured, grinding against him. The Doctor glanced down once to see what Rory was doing, and then turned his attentions back to Amy. He kissed her breasts, teasing her nipples with his teeth, and when she frowned slightly as Rory’s finger pushed into her the Doctor reached for her clit, rubbing in tiny, rapid circles. Rory worked her open carefully, slowly, as she moaned and gasped and swore and ordered both of them not to stop, never to stop, spreading her legs wider with every new stroke of Rory’s fingers.

Finally, Rory just couldn’t hold off any longer. The Doctor’s attentions had Amy quivering on the edge of an orgasm already, biting her lip and making little involuntary noises in the back of her throat. When Rory slicked his throbbing erection and pressed it to her arsehole, she nodded enthusiastically.

“Let’s get this show on the road,” she breathed, getting a hand around behind Rory to push his hips forward.

Rory eased himself in, moaning openly as tight heat enveloped his cock, and as soon as he was all the way in the Doctor pressed harder on Amy’s clit and rolled a nipple between two fingers. Amy came hard, thrashing in their grip, the waves of her orgasm making Rory see stars.

When she had recovered her breath a bit, she grabbed the Doctor’s hips with firm hands.

“And now you,” she said, spreading her legs wider. The Doctor swallowed hard, then lined himself up and thrust into Amy in one stroke. All three of them gasped. After a moment of reshuffling legs and arms and handholds on the sheets, Amy tipped her head back and growled, “Move, you two!”

Rory began thrusting, an easy, gentle rhythm at first. He quickly found that with the Doctor moving at the same speed, a moderate pace was all it was going to take. He and the Doctor were just slightly out of sync, the staggered rhythm making Amy moan. Rory ran his hands up her sides, around to her breasts, down the flat plane of her stomach. She was breathless, head thrown back, and as Rory’s hand arrived at her hip she grabbed it, twining her fingers through his. Rory looked at his wife, then at the Doctor, whose eyes were half-closed, lips brushing the curve of Amy’s neck. Rory reached around and took his hand, bringing their palms together. The Doctor grinned and leaned over Amy to kiss Rory. The movement drove him deeper inside Amy, who moaned, trying to move against both of them at the same time.

“You know how I said before not to stop?” she said. “Now I _really_ mean it.”

The Doctor groaned and picked up the pace, biting at Rory’s lower lip as he did. Rory put his hands, still entwined with his lovers’, on Amy’s hips, rocking into her faster, harder, feeling her heartbeat against his chest and the Doctor’s breath against his cheek. Their bodies were pressed snugly together, but Amy managed to get a finger on her clit. She barely had to touch herself at all before she came again, shuddering between and around her boys. The Doctor made a strangled sound and followed her over the edge, his hips stuttering and slowing as he pulsed inside her. Rory bit his lip harshly, trying to hold on, prolong the pleasure another minute, but Amy’s fingers tightened on his and he was gone.

After a moment, they disentangled themselves, then drew together again, relaxing in a sated, sweat-soaked pile. Rory kissed just behind Amy’s ear and rested his head on her shoulder.  
“Thank you,” he whispered.

“Thank _you_ , she replied. “That was amazing.”

“Yes, that was… blimey,” the Doctor said. “I see why you had trouble describing it.”

Rory laughed softly and squeezed the Doctor’s hand. He might not always be the best at figuring things out, but fortunately, when things went right, they went _really_ right.


End file.
